inal albino parent-variety.

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It is, also, remarkable that Himalayans, though produced so suddenly, breed
true. But as, whilst young, they are albinoes, the case falls under a very
general rule; for albinism is well known to be strongly inherited, as with
white mice and many other quadrupeds, and even with white flowers. But why,
it may be asked, do the ears, tail, nose, and feet, and no other part of
the body, revert to a black colour? This apparently depends on a law, which
generally holds good, namely, that characters common to many species of a
genus--and this, in fact, implies long inheritance in common from the
ancient progenitor of the genus--are found to resist variation, or to
reappear if lost, more persistently than the characters which are confined
to the separate species. Now, in the genus Lepus, a large majority of the
species have their ears and the upper surface of the tail tinted black; but
the persistence of these marks is best seen in those species which in
winter become white: thus, in Scotland the _L. variabilis_[265] in its
winter dress has a shade of colour on its nose, and the tips of its ears
are black: in the _L. tibetanus_ the ears are black, the upper surface of
the tail greyish-black, and the soles of the feet brown: in _L. glacialis_
the winter fur is pure white, except the soles of the feet and the points
of the ears. Even in the variously-coloured fancy rabbits we may often
observe a tendency in these same parts to be more darkly tinted than the
rest of the body. Thus, as it seems to me, the appearance of the several
coloured marks on the Himalayan rabbit, as it grows old, is rendered
intelligible. I may add a nearly analogous case: fancy rabbits very often
have a white star on their foreheads; and the common English hare, whilst
young, generally has, as I have myself observed, a similar white star on
its forehead.

When variously coloured rabbits are set free in Europe, and are thus placed
under their natural conditions, they generally revert to the aboriginal
grey colour; this may be in part due to the tendency in all crossed
animals, as lately observed, to revert to their primordial state. But this
tendency does not always prevail; thus silver-grey rabbits are kept in
warrens, and remain true though living almost in a state of nature; but a
{112} warren must not be stocked with both silver-greys and common rabbits;
otherwise "in a few years there will be none but common greys
su